Materials Literature
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The structure, microstructure, and magnetic properties of nanostructured Sm2Co17-based powders synthesized by mechanically milling and subsequent annealing have been systematically studied. It has been found that a nanoscale 2:17 phase with an average grain size of about 30 nm is developed within the powders, which ha…
In this paper, a frequency-selective structure based on guided-mode resonance effects in all-dielectric waveguide gratings is demonstrated theoretically and verified experimentally. Reflection (band-stop) filters with high efficiency, extended low-sideband reflection, and symmetric line shapes are designed by embeddin…
Ferroelectric properties of the metal/ferroelectric/insulator/semiconductor (MFIS) structure were investigated using the Pt/YMnO3/Y2O3/Si structure. The ferroelectric C–V hysteresis was observed for not only the Pt/YMnO3(0001)/Y2O3/Si capacitor but also the Pt/amorphousYMnO3/Y2O3/Si capacitor. The polarization evaluat…
Ferroelectric properties of a Pb(Zi, Ti)O 3 (PZT) capacitor with thin SrRuO 3 (SRO) films within both electrodes were investigated in detail. Thin SRO films of 10 nm thickness markedly improve the electrical performance, such as switching charge (Qsw), saturation characteristics of the hysteresis curve and imprint per…
Fullerenes and single-wall carbon nanotubes (SWNTs) have been produced for the first time by the high-temperature pulsed arc-discharge technique, which has developed in this laboratory. Fullerenes are identified quantitatively by high-performance liquid chromatography (HPLC), and scanning electron microscopy (SEM) and…
A different phase-separation process is capable of producing a composite system consisting of a very thin layer of liquid crystal in contact with a similarly thin layer of polymer. The morphology of the polymer depends on the composition of the prepolymer-liquid crystal mixture and the rate of polymerization. A simple…
Pyruvate kinase (PK; EC 2.7.1.40) of Thermoproteus tenax was purified to homogeneity, and its coding gene was cloned and expressed in Escherichia coli. It represents a homomeric tetramer with a molecular mass of 49 kDa per subunit. PK exhibits positive binding cooperativity with respect to phosphoenolpyruvate and meta…
We report high-resolution x-ray-absorption near-edge structure measurements at the Mn K edge as a function of temperature, for ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ samples, with a focus mainly on the pre-edge region. Small peaks labeled ${A}_{1}--{A}_{3}$ are observed which correspond…
Iron–carbon nanocomposite thin films with iron concentrations ranging from 12 to 74 at. % were grown by ion-beam sputtering codeposition at different substrate temperatures. The microstructure of the films was characterized by transmission electron microscopy, atomic force microscopy, extended x-ray absorption fine st…
The problem of the low-temperature resistance of granular films of manganites with nanometric grain sizes is addressed. The observed upturn in the low-temperature resistance is understood in terms of charging effects. However, the standard Coulomb blockade scenario does not describe the observed dependence of the char…
The crystallization, transformation, and partitioning of amorphous PbO—ZrO 2 —TiO 2 powders produced by pyrolytic decomposition of partially hydrolyzed, mixed alkoxide precursors were investigated. Materials have the general formulation Pb 1+χ Ti [1/(1+φ)] Zr [φ/(1+φ)] O 3+χ , where −0.2 ≤χ≤ 0.2 is the fraction of PbO…
The crystal structures of the four experimentally observed phases of ${\mathrm{Si}}_{3}{\mathrm{N}}_{4}$ with space groups ${P6}_{3}/m,$ ${P6}_{3},$ ${P3}_{1}/c,$ and ${\mathrm{Fd}}_{3}/m$ are fully optimized by means of first-principles total-energy calculations. The relaxation of all internal parameters is achieved…
The thermal conductivity and the cellular structure as well as the matrix polymer morphology of a collection of chemically crosslinked low-density closed cell polyolefin foams, manufactured by a high-pressure nitrogen gas solution process, have been studied. With the aid of a useful theoretical model, the relative con…
A facile approach to engineering diverse mixed-colloid ensembles is presented here. Various colloid architectures are seen that are controlled by both electrostatic self-assembly and concentration changes (see Figure) regardless of the nature of the nanoparticle core. The methodology should be applicable to the creati…
Neutron-powder-diffraction measurements, combined with magnetization and resistivity data, have been carried out in the doped perovskite ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ $(x=0.47,$ 0.50, and 0.53) to elucidate the structural, magnetic, and electronic properties of the system around…
Abstract Effects of particle size of Al(OH) 3 (ATH) filler on electrical properties of ethylene propylene diene terpolymer (EPDM)/ATH compounds were studied. It was found that tracking and erosion resistance of EPDM/ATH compounds decreased while dielectric properties and 90°C water resistance were improved with the in…
Abstract A model dissolution/reprecipitation process is studied for the recycling of both polyϵ‐caprolactam (PA 6) and polyhexamethyleneadipamide (PA 6 6). This process comprises dissolution of each of the aforementioned polyamides in an appropriate solvent, reprecipitation by addition of a nonsolvent and finally reco…
A new homologous series of thermotropic liquid crystalline poly(azomethine-ether)s was synthesized by solution polycondensation of various diformyl-alpha,omega-diphenoxyalkanes, I-VIII with 2,5-bis(m-aminobenzylidene)cyclopentanone, XI and 2,6-bis(m-aminobenzylidene)cyclohexanone, XII. The inherent viscosities of the…
Abstract We studied the effect of liquid crystal polymer (LCP) and surface modification of neodymium‐iron‐boron (Nd‐Fe‐B) magnetic alloy on the magneto‐mechanical behavior of poly (phenylene sulfide) (PPS) bonded Nd‐Fe‐B magnets to accelerate efforts to develop useful thermoplastic magnets with optimal performance. Th…
Abstract Thermal conductivities of undoped and various protonic acid-doped polyaniline films were measured by combination of a laser flash method and a scanning differential calorimeter. The thermal conductivities thus measured are in the range of conventional organic polymers, indicating that the doped polyaniline fi…